How to declare a variable in JavaScript?

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How to declare a variable in JavaScript?

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Variables are identifiers that are declared to store data in memory temporarily and retrieve them when necessary. In JavaScript, variables are declared by using the var keyword. Different types of variables can be declared by using the var keyword. Variables can be declared inside or outside of the function. When a variable is declared inside the function, it is called a local variable. When it is declared outside the function, it is called a global variable. The life of a global variable ends when the page unloads, while the life of a local variable ends with the end of the execution of the function in which it is declared.

Variables can be declared as follows:

1. String variables


var str=new String("This is a string")
var str="This is a string"


2. Date variables


var dt=new Date()
var dt=new Date(2005,11,29)


3. Numeric variables


var num=22

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